1. Field of the Invention
The present invention relates generally to the automated production of transponder devices, and more particularly to an automated method of manufacturing alternatively sized passive transponder devices using a single tape leadframe design and a bobbin for assembling the transponder.
2. Brief Description of the Prior Art
Transponders have been used for identification purposes for many years in the detection and identification of animate and inanimate objects. Initially, an operator, using a hand-held or other type of transmitter/reader, directs a beam of energy toward the transponder. This energy is usually in the form of an electromagnetic radio wave and acts to charge a minute capacitor, or similar energy storage component, within the transponder device. An integrated circuit, also a component of the transponder, contains identification information pertinent to a particular application. When activated by the electromagnetic wave, the information stored on this chip is electromagnetically retransmitted and can be received by an appropriate receiver thus enabling identification of the transponder device carrier.
Automated production of the transponder devices must overcome considerable difficulties. For example, since reduced size is desirable, an ultra fine copper wire must be wound around a core to operate effectively as an inductive coil. This wire typically has a diameter of only a few microns, and is thus quite difficult to manipulate with precision and care, even manually. Consequently, prior art methods of manufacture require a relatively slow core winding speed, and manual bonding of the wire ends directly to the integrated circuit surface. Thus, operator attention and interaction is continuously required to ensure the proper handling and connection of the delicate core wire. This is very costly, especially in terms of lost production time and the labor expense involved in constantly employing the highly trained technicians necessary for device construction.
Another drawback with prior technology is the difficulty and expense involved in manufacturing transponders of different sizes. This normally requires two distinct manufacturing sites, or, at a minimum, two separate manufacturing cycles and individual production set-ups. This, in turn, increases total production time and overhead, and greatly increases overall operating expenses.